Electronic device with ring-connected hall effect regions

ABSTRACT

An electronic device includes a number of n Hall effect regions with n&gt;1, wherein the n Hall effect regions are isolated from each other. The electronic device also includes at least eight contacts in or on surfaces of the n Hall effect regions, wherein the contacts include: a first and a second contact of each Hall effect region. A first contact of the (k+1)-th Hall effect region is connected to the second contact of the k-th Hall effect region for k=1 to n−1, and the first contact of the first Hall effect region is connected to the second contact of the n-th Hall effect region. The at least eight contacts include at least two supply contacts and at least two sense contacts. Each Hall effect region includes at most one of the at least two supply contacts and at most one of the at least two sense contacts.

RELATED APPLICATION

This application is related to U.S. application Ser. No. 13/187,970filed on Jul. 21, 2011 entitled “VERTICAL HALL SENSOR WITH HIGHELECTRICAL SYMMETRY”.

FIELD OF THE INVENTION

Embodiments of the present invention relate to an electronic device andto a sensing method. In particular, the electronic device may be asensing device for sensing a physical quantity such as a magnetic fieldor a mechanical stress within an object.

BACKGROUND OF THE INVENTION

Electronic devices may be used to sense or measure physical quantities.In order to sense or measure the strength and direction of a magneticfield parallel to the surface of, e.g., a semiconductor die, verticalHall devices may be used. Most vertical Hall devices suffer from thefact that the spinning current method, which is used to cancel thezero-point error of the Hall devices, does not work very well. Withknown methods of the spinning current scheme it is possible to obtainresidual zero point errors of about 1 mT. A reason for this rather pooroffset behavior can be found in the asymmetry of the vertical Halldevice. Although it is known how to connect four vertical Hall devicesin order to improve the symmetry, the contact resistances still causeresidual asymmetries.

Another physical quantity that may be sensed or measured is mechanicalstress within an object such as a substrate, in particular asemiconductor substrate. To this end, an electronic device may be usedthat has a similar structure as a Hall device. Indeed, it may suffice toslightly modify some internal connections of a suitable Hall device inorder to obtain a mechanical stress sensor.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide an electronic devicecomprising a number of n Hall effect regions with n>1, wherein the nHall effect regions are isolated from each other. The electronic devicecomprises at least eight contacts in or on surfaces of the n Hall effectregions. The contacts comprise a first and a second contact of each Halleffect region. A first contact of the (k+1)-th Hall effect region isconnected to the second contact of the k-th Hall effect region for k=1to n−1, and the first contact of the first Hall effect region isconnected to the second contact of the n-th Hall effect region. The atleast eight contacts comprise at least two supply contacts and at leasttwo sense contacts. Each Hall effect region comprises at most one of theat least two supply contacts. Furthermore, each Hall effect regioncomprises at most one of the at least two sense contacts.

Further embodiments of the present invention provide an electronicdevice comprising a first electronic device and a second electronicdevice as defined above, a sense signal evaluator configured to beconnected to a sense contact of the first electronic device and to asense contact of the second electronic device. The sense signalevaluator is further configured to process a differential sense signalthat is based on first and second sense signals provided at the sensecontacts.

Further embodiments of the present invention provide an electronicdevice comprising: a first Hall effect region, a second Hall effectregion, a third Hall effect region, and a fourth Hall effect region thatare isolated from each other. Each Hall effect region comprises a firstcontact, a second contact, a supply contact, and a sense contact in oron surfaces of the Hall effect region. The first contact of the secondHall effect region is connected to the second contact of the first Halleffect region and the first contact of the first Hall effect region isconnected to the second contact of the second Hall effect region, sothat two current paths exist between the supply contact of the firstHall effect region and the supply contact of the second Hall effectregion. The first contact of the fourth Hall effect region is connectedto the second contact of the third Hall effect region and the firstcontact of the third Hall effect region is connected to the secondcontact of the fourth Hall effect region, so that two current pathsexist between the supply contact of the third Hall effect region and thesupply contact of the fourth Hall effect region. The supply contacts andthe sense contacts are arranged in a sequence along each one of thecurrent paths such that there is one sense contact of the sense contactsbetween two of the supply contacts. A first differential sense signal istapped between the sense contacts of the first and third Hall effectregions and a second differential sense signal is tapped between thesense contacts of the second and fourth Hall effect regions.

Further embodiments of the present invention provide an electronicdevice, comprising: four Hall effect regions that are isolated from eachother, wherein each of the four Hall effect regions comprises a firstcontact and a second contact in or on a surface of the Hall effectregion. A first contact of the (k+1)-th Hall effect region is connectedto a second contact of the k-th Hall effect region for k=1 to 3, and afirst contact of the first Hall effect region is connected to a secondcontact of the fourth Hall effect region. Each of the four Hall effectregions further comprises one of a supply contact and a sense contact inor on the surface of the Hall effect region, the supply contact or thesense contact being arranged between the first contact and the secondcontact of the Hall effect region. A Hall effect region in or on thesurface of which a supply contact is formed is connected via its firstand second contacts to two Hall effect regions in or on the surfaces ofwhich a sense contact is formed, respectively, so that the supplycontacts and the sense contacts are arranged in a sequence along acurrent path between at least two supply contacts such that there is onesense contact between the at least two supply contacts. Each Hall effectregion comprises at most one of the at least two supply contacts.

Further embodiments according to the teachings disclosed herein providean electronic device comprising a first Hall effect region and a secondHall effect region, at least four spinning current contacts, and atleast four ring-contacting contacts. The first and second Hall effectregions are isolated from each other. At least one contact of the atleast four spinning current contacts is formed in or on a surface ofeach of the first and second Hall effect regions and configured tofunction as a supply contact and a sense contact during differentoperating phases of a spinning current scheme. Two of the at least fourring-contacting contacts are formed in or on the surface of the firstHall effect region and two of the at least four ring-contacting contactsare formed in or on the surface of the second Hall effect region. The atleast four ring-contacting contacts are pair-wise electrically connectedvia two connections other than the first and second semiconductor Halleffect regions, thus forming at least two pairs. Each pair comprises onering-contacting contact of the first Hall effect region and onering-contacting contact of the second Hall effect region so that thefirst Hall effect region and the second Hall effect region areelectrically connected in a ring-like manner. The at least fourring-contacting contacts and the two connections are configured so thata total current fed to a supply contact of the first Hall effect regionand extracted at another supply contact at the second Hall effect regionis divided in two substantially equal parts flowing via the twoconnections.

Furthermore, embodiments of the present invention provide a sensingmethod, comprising: connecting a power supply between a first supplycontact formed in or on the surface of a first Hall effect region and asecond supply contact formed in or on the surface of another Hall effectregion, the first Hall effect region and the other Hall effect regionbeing part of a number of n Hall effect regions, wherein a first contactof the (k+1)-th Hall effect region is connected to a second contact ofthe k-th Hall effect region for k=1 to n−1, and the first contact of thefirst Hall effect region is connected to the second contact of the n-thHall effect region so that an electric current provided by the powersupply flows via two current paths from the first supply contact to thesecond supply contact.

The method further comprises sensing sense signals at a first sensecontact formed in or on the surface of one of the n Hall effect regionsand at a second sense contact formed in or on a surface of another oneof the n Hall effect regions, wherein each Hall effect region comprisesat most one of the at least two sense contact. Further, the methodcomprises swapping temporary functions of the first supply contact andthe first sense contact and swapping temporary functions of the secondsupply contact and the second sense contact so that the power supply issubsequently connected between the former first sense contact and theformer second sense contact, wherein the electric current flows from theformer first sense contact to the former second sense contact via the nHall effect region. Lastly, the method includes sensing sense signals atthe former first and the former second supply contacts, and determiningan output signal based on sense signals at the first sense contact, thesecond sense contact, the former first supply contact, and the formersecond supply contact.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention are described herein, makingreference to the appended drawings.

FIG. 1 shows a schematic cross-section through an electronic device anda corresponding plan view of the electronic device according to anembodiment of the teachings disclosed herein;

FIG. 2 shows a schematic cross-section through an electronic devicesimilar to the electronic device shown in FIG. 1;

FIG. 3 shows a schematic cross-section through an electronic deviceaccording to a further embodiment of the teachings disclosed herein;

FIG. 4 shows a schematic cross-section through an electronic deviceaccording to yet another embodiment of the teachings disclosed herein;

FIG. 5 shows a schematic cross-section through an electronic deviceaccording to a further embodiment of the teachings disclosed herein;

FIG. 6 shows two schematic plan views of an electronic device accordingto a further embodiment of the teachings disclosed herein during a firstphase and a second phase of a measuring cycle, the electronic devicecomprising four Hall effect regions;

FIG. 7 shows a graph illustrating in a cross-sectional view the electricpotential and the current streamlines within the four Hall effectregions of the embodiment shown in FIG. 6;

FIG. 8 shows a graph illustrating, for three different magnetic fieldvalues, the electric potential at a surface of the four Hall effectregions of the electronic device according to the embodiment shown inFIG. 6 and corresponding to the cross-sectional view the electricpotential shown in FIG. 7;

FIG. 9 shows a schematic plan view of an electronic device according toan embodiment with four Hall effect regions arranged in a line;

FIG. 10 shows a schematic plan view of an electronic device according toan embodiment with four Hall effect regions arranged in a quadrangle;

FIG. 11 shows a schematic plan view of an electronic device according toanother embodiment with four Hall effect regions arranged in aquadrangle;

FIG. 12 shows a schematic plan view of an electronic device according toan embodiment with four Hall effect regions arranged in a quadrangle andwith diagonal ring structures;

FIG. 13 shows a schematic plan view of an electronic device according toa further embodiment with four Hall effect regions arranged in aquadrangle;

FIG. 14 shows a schematic plan view of an electronic device according toan embodiment with four Hall effect regions, two of which are connectedin a first ring and are arranged at an angle of 90 degrees to the othertwo Hall effect regions that are connected in a second ring;

FIG. 15 shows a schematic plan view of an electronic device according toan embodiment with four Hall effect regions similar to the embodimentshown in FIG. 14;

FIG. 16 shows a schematic plan view of an electronic device according toan embodiment, wherein each ring structure comprises two Hall effectregions disposed at an angle of 90 degrees to each other;

FIG. 17 shows a schematic plan view of an electronic device according toan embodiment similar to the embodiment shown in FIG. 16;

FIG. 18 shows a schematic plan view of an electronic device according toan embodiment comprising four Hall effect regions arranged in aquadrangle;

FIG. 19 shows a schematic plan view of an electronic device according toan embodiment similar to the one shown in FIG. 18;

FIG. 20 shows a schematic plan view of an electronic device according toan embodiment combining the embodiments shown in FIG. 2 and FIG. 19;

FIG. 21 shows a schematic plan view of an electronic device according toan embodiment similar to the one shown in FIG. 19;

FIG. 22 shows a schematic plan view of an electronic device according toan embodiment comprising four Hall effect regions arranged in a column;

FIG. 23 shows a schematic plan view of an electronic device according toanother embodiment comprising four Hall effect regions arranged in acolumn;

FIG. 24 shows two schematic plan views of an electronic device accordingto an embodiment of the teachings disclosed herein during a first phaseand a second phase of a measuring cycle, the electronic devicecomprising four Hall effect regions, each having a single spinningcurrent contact;

FIG. 25 shows a cross sectional view of the electronic device accordingto an embodiment of the teachings disclosed herein and a graphillustrating in a cross-sectional view the electric potential and thecurrent density within the four Hall effect regions;

FIG. 26 shows a graph illustrating the electrical potential at twodifferent contacts over the magnetic field strength; and

FIG. 27 shows a schematic flow diagram of a sensing method according toan embodiment of the disclosed teachings.

Equal or equivalent element or elements with equal or equivalentfunctionality are denoted in the following description by equal orsimilar reference signs.

DETAILED DESCRIPTION

In the following description, a plurality of details are set forth toprovide a more thorough explanation of embodiments of the teachingsdisclosed herein. However, it will be apparent to one skilled in the artthat embodiments of the teachings disclosed herein may be practicedwithout these specific details. Features of the different embodimentsdescribed hereinafter may be combined with each other, unlessspecifically noted otherwise. For the most part, the terms “Hall effectregion” and “tub” are used interchangeably herein. Accordingly, a Halleffect region may be a tub or well of a first conductivity type which isembedded in a substrate or a tub of opposite conductivity type. Thisstructure may cause an electrical isolation of the tub against thesubstrate in particular if the resulting pn-junction is reverse biased.However, it may also be possible that one tub comprises two or more Halleffect regions, in particular when two or more relatively distinctcurrent flows can be created within the Hall effect region (thuseffectively providing some sort of isolation of the two Hall effectregions).

When the electronic device comprises two or more Hall effect regions,these may be isolated from each other. The electrical isolation of twoHall effect regions against each other may take several forms. Accordingto a first form of isolation, the two or more Hall effect regions aredisjoined from each other, i.e., two adjacent Hall effect regions do notmerge at one or more locations but are separated by a material otherthan the Hall effect region material. As one possible option, the tubmay be isolated in lateral direction by means of trenches that aretypically lined and/or filled with a thin oxide. As another option, thetub may be isolated towards the bottom by means of an SOI (silicon oninsulator) structure. Although the tub typically has a singleconductivity type it may be advantageous to configure the dopingconcentration in an inhomogeneous manner, i.e. spatially variable. Inthis manner a high concentration of the doping agent may occur in thearea of the contacts, as is usual with deep CMOS tub contacts. In thealternative, a layering of differently strongly doped layers may besought after, as is the case with e.g. a buried layer. Such a layeringmay result, to some extent, from technological reasons relative to otherelectronic structures that are formed within the substrate. The designof the electronic device, the Hall device, or the mechanical stresssensor then may need to be reconciled with these circumstances, eventhough the layering may in fact be unfavorable for the electronicdevice, the Hall device, or the mechanical stress sensor.

Another form of isolation may be achieved by measures that reduce orsubstantially prevent an electric current from flowing in one or moresubregions of a tub or well. For example, the electric current may beoffered an alternative current path that has lower ohmic resistance(possibly by several orders of magnitude) than a substantially parallelcurrent path would have that goes through the tub. The current pathhaving the lower ohmic resistance may be a conductor formed in or on thesurface of the tub.

In one embodiment, the Hall effect region may be an n-dopedsemiconductor as this provides a three times higher mobility andconsequently a higher Hall factor than with a p-doped semiconductor. Thedoping concentration in the functional part of the Hall effect region inone embodiment is typically in the range of 10¹⁵ cm⁻³ to 10¹⁷ cm⁻³.

Another possible material for the Hall effect regions is permalloy whichis a nickel-iron magnetic alloy, or a material similar to permalloy.Permalloy exhibits a low coercivity, near zero magnetostriction, highmagnetic permeability, and significant anisotropic magnetoresistance. Avariation of the electrical resistance of permalloy within a range ofapproximately 5% can typically be observed depending on the strength andthe direction of an applied magnetic field. This effect may be used in asimilar manner as the Hall effect occurring in a semiconductor forsensing and/or measuring a magnetic field, and is known in theliterature as the anomalous Hall effect.

The teachings disclosed herein are related to the use of the spinningcurrent principle, in which supply- and sense-terminals are exchanged inconsecutive clock phases/operating phases. A sense terminal in avertical Hall device responds to an electric current passing underneathit. A magnetic field (parallel to the die surface and perpendicular tothe current streamlines) can efficiently lift up or pull down thepotential at the contact (which typically is at the surface of the die).The term “vertical Hall effect” or “vertical Hall device” may be thoughtof as being derived from the fact that the Hall effect in a verticalHall device acts in a vertical direction (if the surface of thesubstrate is assumed to be horizontal, per definition). Contacts at theend of a tub (or semiconductor Hall effect region) typically are not, oronly negligibly, subject to current streamlines passing underneath them.Therefore, contacts at the ends of a tub typically are less frequentlyused as sense contacts. Besides a classification of Hall devices in“horizontal Hall devices” and “vertical Hall devices” they may also bedistinguished regarding the direction in which the current flows in aregion where it experiences the Hall effect. In a Hall device using the“vertical current mode”, the electric current substantially flows in avertical direction with respect to the surface (which is assumed to behorizontal). In a Hall device using the “horizontal current mode”, theelectric current substantially flows in a horizontal direction, i.e.,parallel to the (horizontal) substrate surface, at least in a regionwhere the Hall effect acts on the electric current and can be sensed.The electronic devices according to the teachings disclosed hereintypically (but not necessarily) use a substantially horizontal currentmode. According to the disclosed teachings it is proposed that theelectrical equivalent of the device is an electrical ring. In this wayit can be avoided that the distance of the supply contacts to the end ofthe Hall effect region changes in a significant manner during a spinningclock cycle because a ring does not have an outer edge.

As it is described in the abstract, an electronic device comprises anumber of n Hall effect regions with n>1, wherein the n Hall effectregions are isolated from each other. The electronic device alsocomprises at least eight contacts in or on a surface of the n Halleffect regions, wherein the contacts comprise a first and a secondcontact of each Hall effect region. A first contact of the (k+1)-th Halleffect region is connected to the second contact of the k-th Hall effectregion for k=1 to n−1, and the first contact of the first Hall effectregion is connected to the second contact of the n-th Hall effectregion. The at least eight contacts comprise at least two supplycontacts and at least two sense contacts. Each Hall effect regioncomprises at most one of the at least two supply contacts and at mostone of the at least two sense contacts.

The Hall effect regions are formed in an isolated manner from each other(for example in the same substrate, having an insulating structure or atleast a substantially current-free region between them, or in twodistinct substrates) but galvanically connected to a ring thus forming aring structure. An electric current enters the ring structure at a firstsupply contact and leaves the ring structure at a second supply contact.Due to the ring structure, two current paths are available for theelectric current between the first supply contact and the second supplycontact. The two current paths begin at the first supply contact andjoin together at the second supply contact. Typically it will beaimed-at that the two current paths are substantially equal orsymmetrical with respect to their electric properties such asresistance, capacitance, inductance, etc. The electric current willbranch into two substantially equal partial currents, if the two currentpaths are substantially equal or symmetrical. The term “ring” thusdescribes the topology of the current flow. In order to make a roundtripalong the ring, one would first follow the first current path from thefirst supply contact to the second supply contact. Then one would followthe second current path from the second supply contact back to firstsupply contact. Note that on the second leg of the roundtrip thedirection of travel is opposite to the direction of current flow, whichis in accordance with the definition of a ring structure according tothe disclosed teachings.

A spinning current scheme may be used in particular in case theelectronic device is a vertical Hall effect device. During the executionof one cycle of the spinning current scheme, a first ring is formedduring a first operating phase of the spinning current cycle, and asecond ring is formed during a second operating phase of the spinningcurrent cycle. The two rings of the two operating phases differ inparticular with respect to the contacts where the electric currententers and leaves the ring. In each operating phase at least sixcontacts are typically within the ring: the two supply contacts and fourring-contacting contacts which serve to connect the n (i.e., two ormore) Hall effect regions to each other. With respect to any sensecontacts that are formed in or on the surface of the Hall effect regionsit can be said that, although a main purpose of the sense contacts isnot to be traversed by the electric current, they nevertheless influencethe current flow through the substrate. Indeed, as the sense contactstypically have a lower resistance than the surrounding substrate, aportion of the electric current may actually flow through the sensecontacts in a transverse manner.

The proposed ring connection differs from a parallel connection of twoor more Hall effect regions as explained in the following. In a parallelconnection two or more nodes of one Hall effect region are electricallyconnected to two or more corresponding nodes of the other Hall effectregion. In this manner, the electric potential at these nodes is alignedbetween the two or more Hall effect regions. The two or more Hall effectregions of a parallel connected configuration are not part of a commonmain current path, i.e. an electric current fed to the first Hall effectregion at a first supply contact does not mainly flow through the secondHall effect region, but typically leaves the first Hall effect region ata second supply contact with substantially the same magnitude. Bycontrast, in the ring connection which is proposed herein a totalelectric current is split into two (substantially equal) parts withinone of the Hall effect regions, i.e. the Hall effect region in which oron the surface of which the first supply contact is currently formed.The parts of the total electric current flow to at least one other Halleffect region. Subsequently, the parts of the total electric currentflow through the at least one other Hall effect region and eventuallyjoin together just before leaving the ring structure at the secondsupply contact. In this manner, the part of the total electric currentthat leaves one of the Hall effect regions via the first contact or thesecond contact of the Hall effect region enters the other Hall effectregion so that both Hall effect regions see the same part of the totalelectric current at the contact via which the connection is made.

In some configurations a conductive region, such as an n+ buried layer(nBL), may be present adjacent to a second surface of the Hall effectregions opposite to the first surface. According to the teachingsdisclosed herein, the contacts that are formed in the first surface(s)or on the first surface(s) of the Hall effect region(s) are electricallyseparated from the conductive region. In particular, no low-ohmicconnection, such as one or more n+ sinker(s), exists between one of theat least eight contacts and the conductive region (e.g., the nBL).Rather, the contacts and the conductive region are separated by at leasta portion of the relatively high-ohmic Hall effect region. In otherwords, an electrical connection between one of the at least eightcontacts and the conductive region traverses the corresponding Halleffect region or a portion thereof (typically in a vertical direction).

FIG. 1 shows a schematic cross-section through an electronic device 10according to an embodiment of the teachings disclosed herein and, belowthe schematic cross section, a schematic plan view of the sameelectronic device. The electronic device 10 comprises a first Halleffect region 11 and a second Hall effect region 12. The Hall effectregions 11 and 12 may be formed in a semiconductor substrate by locallydoping the semiconductor substrate to obtain e.g. an n-typesemiconductor material (an n-type semiconductor has more electrons thanholes). A supply contact 21 and a sense contact 23 are formed on asurface of the first Hall effect region 11. A supply contact 22 and asense contact 24 are also formed on a surface of the second Hall effectregion 12. The supply contacts 21, 22 and the sense contacts 23, 24 arespinning current contacts that are configured to function as supplycontacts during a first operating phase of a spinning current cycle andto function as sense contacts during a second operating phase of thespinning current cycle, or vice versa. FIG. 1 depicts the electronicdevice in a configuration corresponding to a first clock phase of thespinning current cycle. An electric current enters the first Hall effectregion 11 at the spinning current contact 21 (first supply contact) andleaves the second Hall effect region 12 at the spinning current contact22 (second supply contact) that is, in the depicted configuration,connected to a ground potential. The two spinning current contacts 23and 24 are configured to function as sense contacts during the firstclock phase. In a second clock phase, the two spinning current contacts23 and 24 are configured to function as supply contacts and the previoussupply contacts 21 and 22 are configured to function as sense contacts.Therefore it may be advantageous to have a high degree of symmetrybetween contacts 21 and 23 as well as between contacts 22 and 24.

The electronic device 10 shown in FIG. 1 further comprises fourring-contacting contacts 31, 32, 33, and 34. In other parts or textpassages of the present disclosure, the ring-contacting contacts arealso referred to as “first contact” and “second contact” of acorresponding Hall effect region. The ring-contacting contacts 31 and 34are electrically connected by means of an electrically conductingconnection 41. The ring-contacting contacts 32 and 33 are electricallyconnected to each other by means of another electrically conductingconnection 42. In this manner, the two Hall effect regions 11 and 12 areconnected in a ring-like manner. The ring-contacting contacts aredistinct from the spinning current contacts. In FIG. 1, thering-contacting contacts 31 to 34 are located closer to an end of one ofthe Hall effect regions 11, 12 than the spinning current contacts 21 to24. This causes the electric current input at the spinning currentcontact 21 during the first clock phase to flow along a first currentpath of the ring and along a second current path of the ring until itleaves the ring at the spinning current contact 22. Another observationthat can be made is that the electric current enters and leaves the twoHall effect regions 11, 12 at the same contacts where it enters andleaves the electrical ring structure. In other words, the electriccurrent flowing through the electronic device between the two supplycontacts 21, 22 is conducted along the ring structure. Typically, thereare two conducting paths (current paths) between the two supply contacts21 and 22 and the electric current will assume a current distributioncorresponding to the resistances of the two conducting paths. The firstconducting path leads from the supply contact 21 to the right, via thering-contacting contacts 32 and 33 and connection 42 to the secondsemiconductor region 12, beneath (and possibly partly through) the sensecontact 24 and finally to the supply contact 22. The second conductingpath leads from the supply contact 21 to the left, beneath (and possiblypartly through) sense contact 23, via the ring-contacting contacts 31and 34 and the connection 41 to the second Hall effect region 12 andfinally to the supply contact 22. The first conducting path and thesecond conducting path each comprise sections traversing the Hall effectregions 11, 12. In the embodiment shown in FIG. 1, the total lengths ofthe sections within the first and second Hall effect regions areapproximately equal for the first and second conducting paths. Theconnections 41 and 42 may be relatively low ohmic compared to the Halleffect regions 11, 12. All this leads to a substantially balancedcurrent distribution among the first and second conducting paths.Furthermore, the ring-contacting contacts 31 to 34 may be relativelylarge in order to make the connection to the ring low-ohmic and toreduce the voltage drop across the ring-contacting contacts 31 to 34. Atleast one of the two ring-contacting contacts may have a large effectivesurface for a low-ohmic connection between the at least onering-contacting contact and the Hall effect region.

The electric currents flow in the same direction via the connections 41and 42, i.e., from the first Hall effect region 11 to the second Halleffect region 12. The supply contact 21 at which the electric currententers the Hall effect regions 11, 12 is provided at the first Halleffect region 11, while the current supply contact at which the electriccurrent leaves the Hall effect regions 11, 12 is provided at the secondHall effect region 12. The direction in which the current flows throughthe semiconductor Hall effect device regions 11, 12, where it enters,and where it leaves the electronic device is basically a design optionand may be modified. Moreover, the direction of the current could beinversed e.g. during an optional third operating phase and an optionalfourth operating phase of the spinning current scheme. One effect of thering connection is that the electric current passes in oppositedirections beneath the sense contacts 23, 24 so that, due to the Halleffect, the electrical potential at one of the sense contacts increasesas a result of a magnetic field being present, while the electricalpotential at the other sense contact decreases. However, the two sensecontacts are at different common mode potentials. This means that (even)without a magnetic field being present the electrical potentials at thesense contacts 23 and 24 are generally not equal: The electricalpotential at the sense contact 23 is closer to an electric potential ofa positive pole of the power supply (which is connected to the supplycontact 21), whereas the electrical potential at the sense contact 24 iscloser to the ground potential (which is connected to the supply contact22).

The first and second Hall effect regions may be symmetrical with respectto a symmetry axis or a symmetry plane. The two ring-contacting contactsof the first Hall effect region and the two ring-contacting contacts ofthe second Hall effect region may be symmetrical with respect to thesymmetry axis or the symmetry plane, as well. In FIG. 1 for example, afirst symmetry axis or symmetry plane for the electronic device may belocated between the first Hall effect region 11 and the second Halleffect region 12, and a second symmetry axis or symmetry plane for onlythe Hall effect region 11 may be located between contacts 21 and 23.With respect to the symmetry of the electronic device 10, it should benoted that it may typically not be necessary to distinguish betweensupply contacts and sense contacts, as these typically are onlytemporary functions of the corresponding spinning current contacts.Rather, for the purpose of assessing a symmetry of the electronicdevice, a distinction may typically be made between spinning currentcontacts and ring-contacting contacts.

As can be seen in FIG. 1 and some of the subsequent Figures, the firstand second Hall effect regions 11, 12 may be disposed along a line. Theline may extend along the longitudinal axes of the first and second Halleffect regions 11, 12 so that the longitudinal axes substantiallycoincide. The first and second semiconductor Hall effect devices are inthis case longitudinally offset. Hence, the first end of the first Halleffect region 11 and the second end of the second Hall effect region 12are exterior ends and the second end of the first Hall effect region 11and the first end of the second Hall effect region 12 are interior endswith respect to the electronic device structure.

The electronic device 10 shown in FIG. 1 comprises two Hall effectregions, i.e. n=2. The supply contact 21 of the at least two supplycontacts 21, 22 is formed in or on the surface of the first Hall effectregion 11 and the other supply contact 22 of the at least two supplycontacts 21, 22 is formed in or on the surface of the second Hall effectregion 22. Moreover, a sense contact 23 of the at least two sensecontacts 23, 24 is formed in or on the surface of the first Hall effectregion 11 and another sense contact 24 of the at least two sensecontacts 23, 24 is formed in or on the surface of the second Hall effectregion 12.

In the electronic device 10 shown in FIG. 1 the first Hall effect region11 comprises a first end and a second end. Likewise, the second Halleffect region 12 comprises a first end and a second end. The firstcontacts 31, 33 and the second contacts 32, 34 are closer to one of thefirst end and the second end of a corresponding one of the first andsecond Hall effect regions 11, 12, than the any one of the supplycontacts 21, 22 and the sense contacts 23, 24 (during the firstoperating phase).

Another way to describe the electronic device 10 depicted in FIG. 1 isas follows: The electronic device comprises two Hall effect regions 11,12. In the first Hall effect region 11, or on a surface thereof, atleast one inside contact (or inner contact or interior contact) isformed. In the embodiment shown in FIG. 1, two inside contacts 21, 23are formed on the surface of the first Hall effect region 11. The secondHall effect region 12 also comprises at least one inner contact, and inparticular two inner contacts 22, 24 that are formed at the surface ofthe second Hall effect region 12. The inner contacts 21 to 24 areconfigured to function as supply contacts and, in an alternating manner,as sense contacts. The inner contacts 21 to 24 belong to at least fourspinning current contacts of which at least one contact is formed in oron the surface of the first and second Hall effect regions. The innercontacts 21 to 24 are configured to function as a supply contact and asense contact during different operating phases of the spinning currentscheme. Furthermore, the first Hall effect region 11 comprises twomargin contacts 31, 32. The second Hall effect region 12 comprises twoother margin contacts 33, 34. The margin contacts 31 to 34 belong to atleast four ring-contacting contacts (also designated as first contactand second contact of a Hall effect region), two of which are formed inor on the surface of the first Hall effect region and two of which areformed in or on the surface of the second Hall effect region. Theconnections 41 and 42 connect the two margin contacts belonging todifferent Hall effect regions in a pair-wise manner, i.e. connection 41connects the margin contacts 31 and 34 whereas connection 42 connectsthe margin contacts 32 and 33. Thus, each pair comprises onering-contacting contact of the first Hall effect region and onering-contacting contact of the second Hall effect region so that thefirst and second Hall effect regions are electrically connected in aring-like manner. The at least four ring-contacting contacts and the twoconnections are configured so that a total current fed to a supplycontact of the first Hall effect region and extracted at another supplycontact at the second Hall effect region (or vice versa) is divided intwo substantially equal parts (with respect to magnitude) flowing viathe two connections. The terms “margin contact” and “inside contact”refer to the relative position of the contacts that are arranged in oron the surface of the Hall effect regions 11 and 12: an “inside contact”typically has at least two neighbors, for example, either (i) two otherinside contacts, or (ii) two margin contacts, or (iii) one other insidecontact and one margin contact. A margin contact is typically locatedcloser to a particular end of the Hall effect region at hand than anyother contact and typically has only one neighboring inside contact.

FIG. 2 shows a schematic cross-section through an electronic device 2according to an embodiment of the teachings disclosed herein. Acorresponding plan view can be readily derived from the schematiccross-section in FIG. 2 in an analogous manner as in FIG. 1. The twoHall effect regions 11 and 12 are arranged within a single long tub withlarge outer contacts 31, 34 and one large contact 32 in the center.Although in a single tub, the two Hall effect regions may be regarded asbeing isolated from each other, in particular when considering themanner in which an electric current flows through the tub. The largecontact 32 may have a lower resistance than the tub so that a vastmajority of the electric current effectively flows through the contact32, in particular if the contact 32 is relatively long and if no n⁺buried layer (nBL) is present. Under this definition, the two Halleffect regions 11, 12 are isolated although they are physically mergedas one large tub. In other words, a low-ohmic path is offered in theform of the contact 32 (corresponding to the contacts 32, 33 and theconnection 42 in FIG. 1) for the electric current, causing the electriccurrent to substantially avoid the tub beneath the contact 32 (thuscreating a substantially current-free region) that achieves an effectiveisolation of the left and right tub portions. Typically, the longer thecontact 32 is in the x-direction, the better the electric isolation(according to the definition given above) between the left and righttubs. The spinning current contacts 21 to 24 are connected in a mannercorresponding to the first clock phase of the spinning current cycle.Compared to the embodiment shown in FIG. 1 the electronic device 2 shownin FIG. 2 has slightly reduced symmetry, yet uses up less space. Thereason for the slightly reduced symmetry is that one of the twoconducting paths along the ring structure comprises an externalconnection in the form of the connection 41, while the other conductingpath is closed by merging the two ring-contacting contacts 32, 33 shownin FIG. 1 to a single ring-contacting contact 32 in FIG. 2. The lengthof the ring-contacting contacts 31, 32 and 34 should be larger than thedepth of the well, i.e. the Hall effect region 11. The centerring-contacting contact 32 typically has a higher electricalconductivity than the material within the Hall effect region 11 so thatthe electric current flowing from the supply contact 21 to the supplycontact 22 flows mostly within the ring-contacting contact 32 instead ofbeneath it. The first Hall effect region 11 and the second Hall effectregion 12 substantially merge at one of their first ends and secondends, respectively. In the present case, the first and second Halleffect regions 11 and 12 merge at their ends that are facing each otherin FIG. 1. The first ring-contacting contact 32 formed in or on thesurface of the first Hall effect region 11 and the corresponding firstring-contacting contact 33 formed in or on the surface of the secondsemiconductor Hall effect region 12 merge as well. Alternatively, thelarge contact 32 depicted in FIG. 2 could be divided into two smallercontacts 32, 33 similar to the ones illustrated in FIG. 1. These twosmaller contacts could then be connected by means of a wire, i.e., theconnection 42. This means that the configuration of FIG. 1 is onlyslightly modified by approaching the Hall effect regions 11 and 12 toeach other until they merge. The contacts 32 and 33 are, however,slightly retracted from the end of the Hall effect regions 11, 12 sothat the contacts 32, 33 do not merge. The resulting electronic devicewould have a better symmetry than the one shown in FIG. 2 as the currentfrom the Hall effect region has to flow via the connections 41 and 42.The larger a spacing between the contacts 32 and 33, the better theisolation between the left and right tub portions.

FIG. 3 shows a schematic cross-section through an electronic device 10according to a further embodiment of the teachings disclosed herein. Acorresponding plan view can be readily derived from the schematiccross-section in FIG. 3 in an analogous manner as in FIG. 1. In contrastto the embodiment shown in FIG. 1 the ring-contacting contacts 31 to 34(which are also called first and second contacts elsewhere) are notflush with ends of the tubs 11, 12. The two ring-contacting contacts,e.g. ring-contacting contacts 31 and 32 or 33 and 34 or all fourcontacts 31 to 34 of at least one of the first and second Hall effectregions 11, 12 are disposed at a distance from the first end and thesecond end of the Hall effect region in or on the surface of which theyare formed. In the electronic device 2 shown in FIG. 2, the outercontacts 31 and 34 also are not flush with the ends of the tub 11, butthey could be. By moving the ring-contacting contacts 31 to 34 slightlyaway from the ends of the Hall effect region(s) 11, 12, boundary effectsacting on the current distribution within the Hall effect region(s) 11,12 can be expected to be reduced. The boundary effects may be differentat a first end and a second end due to fabrication inaccuracies, thusbeing a potential source for asymmetry. Especially when the Hall effectregions 11, 12 are formed by means of locally doping a semiconductorsubstrate, the ends of the Hall effect regions 11, 12 may be subject tomanufacturing tolerances that may possibly affect the currentdistribution. Due to the non-linear voltage-current relationship insemiconductors these asymmetries may lead to residual offset of thespinning current principle. By residual offset we mean that thecombination of measured output voltages in respective operating phasesof the spinning current sequence is not entirely free of zero-pointerror. Therefore asymmetries in the electronic device should be reducedas much as possible.

FIG. 4 shows a schematic cross-section through an electronic device 10according to another embodiment of the teachings disclosed herein. Acorresponding plan view can be readily derived from the schematiccross-section in FIG. 4 in an analogous manner as in FIG. 1. At leastone of the two ring-contacting contacts (or margin contacts) 31, 32, 33,34 per Hall effect region 11, 12 comprises two or more contact sectionsseparated by an interstice. In the embodiment according to FIG. 4, thelarge contacts 31 to 34 shown in FIGS. 1 to 3 have been replaced withseveral smaller ones that are partly floating or shorted by wires. Theseveral smaller contacts are typically separated by an interstice or agap that may be filled with oxide according to state of the art inmodern CMOS/BiCMOS processes or similar technologies. Thus, the largecontacts shown in the previous FIGS. 1 to 3 have been split up intoseveral smaller ones that are either partly floating or shorted withwires. The electronic device 10 of FIG. 4 comprises two short-circuitedring-contacting contacts 31 near a first end of the first Hall effectregion 11, two short-circuited ring-contacting contacts 32 near a secondend of the first Hall effect region 11, two short-circuitedring-contacting contacts 33 near a first end of the second Hall effectregion 12, and two short-circuited ring-contacting contacts 34 near asecond end of the second Hall effect region 12. Furthermore, theelectronic device 10 comprises a plurality of floating contacts 51, 52,53, and 54, that may be considered to be a part of the ring-contactingcontacts (or the margin contacts) 31 to 34. The floating contacts 51 to54 are located at the surface of one of the two Hall effect regions 11,12 between one of the ring contacting contacts 31 to 34 and an end ofsaid one of the two Hall effect regions 11, 12 that is closest to thering-contacting contact in question. The floating contacts may cause thecurrent distribution within the Hall effect region to be more evenlydistributed or uniform and hence to be more symmetrical. Additionalfloating contacts may also be placed between margin contacts and innercontacts or between inner contacts. They may be used to pull the currentcloser to the surface, which may be particularly advantageous if thesemiconductor process has some highly conducting buried layer. Theelectronic device 10 may comprise at least one floating contact formedin or on the surface of at least one of the first and second Hall effectregions 11, 12.

The electronic device 10 may comprise an n⁺-doped buried layer (nBL)that is not depicted in a majority of the Figures. Nevertheless, ingeneral, any electronic device according to the teachings disclosedherein may comprise an n⁺-doped buried layer, unless explicitly statedotherwise.

FIG. 5 shows a schematic cross-section through an electronic deviceaccording to a further embodiment of the teachings disclosed herein. Acorresponding plan view can be readily derived from the schematiccross-section of FIG. 5 in an analogous manner as in FIG. 1. Theelectronic device 10 comprises a buried layer 71, 72 beneath the firstand second Hall effect regions 11, 12. Floating contacts 61, 62, 63, 64,65, and 66 are introduced to prevent an excessive amount of the currentfrom flowing downwards into the buried layer 71, 72.

At the first Hall effect region 11 and starting from the left, thefloating contact 63 is arranged between the ring-contacting contact 31and the spinning current contact 23. The floating contact 61 is arrangedbetween the spinning current contact 23 (sense contact) and the spinningcurrent contact 21 (supply contact). The floating contact 65 is arrangedbetween the spinning current contact (supply contact) 21 and thering-contacting contact 32.

At the second semiconductor Hall effect region 12 and starting from theleft, the floating contact 66 is arranged between the ring-contactingcontact 33 and the spinning current contact (sense contact) 24. Thefloating contact 64 is arranged between the spinning current contact 24(sense contact) and the spinning current contact 22 (supply contact).The floating contact 62 is arranged between the spinning current contact(supply contact) 22 and the ring-contacting contact 34.

During the first operating phase, the two current supply contacts 21 and22 are located in two different Hall effect regions. The same is truefor the two supply contacts 23 and 24 during the second operating phase.An advantage of this configuration becomes apparent when the Hall effectregions comprise, or are adjacent to, a buried layer: Each Hall effectregion may have its own buried layer so that no direct short circuit iscreated via a common buried layer between the two supply contacts 21 and22, or 23 and 24. In contrast, if both supply contacts 21 and 22, or 23and 24 would be arranged at the same Hall effect region, or if two Halleffect regions share a common buried layer, a short circuit between thetwo supply contacts could occur via the buried layer: the buried layerwould then typically be at an electrical potential approximately equalto half the supply voltage (referred to the negative power supplypotential of the power supply). With the proposed structure of havingthe supply contacts in or on the surface of different Hall effectregions (and no common continuous buried layer), the short circuit is atleast strongly reduced, because the buried layer of the Hall effectregion connected to the positive power supply potential is pulled toapproximately ⅔ of the supply voltage and the other buried layer of theother Hall effect region, which is connected to the negative powersupply potential is pulled to approximately ⅓ of the supply voltage(both referred to the negative power supply potential of the powersupply). Hence, the short circuit effect of the buried layer is reducedby separating the buried layer into two non-connected buried layers.Typically, one tries to avoid the short circuit via the buried layer assuch a short circuit consumes much current, yet only contributes littleto the Hall effect.

FIG. 6 shows two schematic top or plan views of an electronic device 100according to a further embodiment of the teachings disclosed hereinduring a first phase (top) and a second phase (bottom) of a measuringcycle, the electronic device 100 comprising four Hall effect regions 11,12, 13, 14. Corresponding cross section views can be readily derivedfrom the schematic plan views in FIG. 6 in an analogous manner as inFIG. 1. This embodiment, among others, fulfils the following tworequirements:

(1) A current is allowed to pass underneath a sense contact.Accordingly, a magnetic field (parallel to the die surface andperpendicular to the current streamlines) can efficiently lift up orpull down the electric potential at the sense contact (which is at thesurface of the die).

(2) The electrical equivalent of the device is an electrical ring. Thusit is avoided, or at least reduced, that the distance of outmost supplycontacts to the end of the device changes during a spinning currentclock cycle.

As can be seen in FIG. 6, the electronic device 100 further comprises athird Hall effect region 13 and a fourth Hall effect region 14 that areelectrically connected in a ringlike manner similar to the first Halleffect region 11 and the second Hall effect region 12. Actually, thefirst and second Hall effect regions 11, 12 and their associatedcontacts and connections form a first basic electronic device 10-1corresponding to the one shown in FIG. 1 and described in connectiontherewith. Likewise, the third and fourth Hall effect regions 13, 14 andtheir associated contacts and connections form a second basic electronicdevice 10-2 similar to the one shown in FIG. 1. The difference betweenthe first and second basic electronic devices 10-1, 10-2 is that in thesecond basic electronic device 10-2 (illustrated in the right half ofFIG. 6) the supply contacts 25, 26 and the sense contacts 27, 28 areswapped when compared to the first basic electronic device 10-1 which isillustrated in the left half of FIG. 6. The first and second Hall effectregions 11, 12, associated spinning current contacts 21 to 24, andassociated ring-contacting contacts 31 to 34 form a first ringstructure. The third and fourth Hall effect regions 13, 14, associatedspinning current contacts 25 to 28, and associated ring-contactingcontacts 35 to 38 form a second ring structure. An output signal of theelectronic 100 device is determined on the basis of a first electricalpotential within the first ring structure or basic electronic device10-1 (for example at the sense contact 23 during the first operatingphase) and a second electrical potential within the second ringstructure or basic electronic device 10-2 (for example at the sensecontact 27 during the first operating phase). The configuration shown inFIG. 6 may be regarded as a longitudinal configuration.

The electronic device 100 shown in FIG. 6 has four tubs or Hall effectregions 11, 12, 13, and 14. The tubs 11 to 14 are isolated from eachother. Each tub has four contacts: two outer contacts 31 and 32, 33 and34, 35 and 36, 37 and 38 and two inner contacts 23 and 21, 24 and 22, 27and 25, 28 and 26. The tubs are pairwise connected with wires 41, 42 and43, 44, respectively, in an electrical ring shape via their outercontacts (ring-contacting contacts) 31 to 38. Both rings are isolatedfrom each other. The upper picture illustrates how the electronic device100 is connected to an electrical supply during a first clock phase ofthe spinning current cycle. In the left ring or first basic electronicdevice 10-1 (comprising the tubs 11 and 12) the supply terminals 21 and22 are the right ones of the inner contacts and the sense terminals 23and 24 are the left ones of the inner contacts. In the right ring orsecond basic electronic device 10-2 the supply terminals 25 and 26 arethe left ones of the inner contacts and the sense terminals 27 and 28are the right ones of the inner contacts. Thus the supply and senseterminals 21 to 28 are inner contacts whereas the tubs 11 to 14 areconnected in a ring via the outer contacts 31 to 38—therefore thecurrent may pass underneath each of the inner contacts 21 to 28, if itis currently used as the sense contact.

The two rings or basic electronic devices 10-1, 10-2 may be tiedtogether with shorts 81 and 82, that are shown as broken lines: theouter contacts 31, 34 and 36, 37, that are closer to the groundterminals 22 and 26 in both basic electronic devices 10-1, 10-2 areconnected. Similarly the outer contacts 32, 33 and 35, 38, that arecloser to the supply terminals 21 and 25 in both basic electronicdevices 10-1, 10-2 are connected. Thus, an electronic device 100 mayfurther comprise at least one electrical cross connection between one ofthe ring-contacting contacts of first basic electronic device 10-1 andan equivalent ring-contacting contact of the ring-contacting contacts ofthe second basic electronic device 10-2. Note that as long as thedevices are identical (no mismatch) there is no current flowing over thelines 81, 82. Therefore, the arrangement can still be regarded ascomprising two separate ring structures.

The supply terminals 21, 22, 25, and 26 may be connected to voltagesupplies or to current supplies—in the latter case the two terminals maybe tied together or not.

The lower picture in FIG. 6 shows how the electronic device 100 may beconnected during a second clock phase of the spinning current cycle. Thespinning current contacts 23, 24, 27, and 28 now function as supplycontacts, whereas the spinning current contacts 21, 22, 25, and 26function as sense contacts.

In accordance with the embodiment shown in FIG. 6, the output voltage(s)or signal(s) is/are not tapped between the two tubs of the same basicelectronic device 10-1, 10-2, but between tubs belonging to differentbasic electronic devices 10-1, 10-2. In particular, the differentialoutput voltages/signals typically are tapped at different common modepotentials. The two additional tubs 13, 14 of the second ring structurefulfill a function of generating differential output voltages.

FIG. 7 shows a graph illustrating in a cross-sectional view the electricpotential and the current streamlines within the four Hall effectregions 11 to 14 of the embodiment shown in FIG. 6 with connections asin phase 1 and without shorts 81 and 82. The graph shown in FIG. 7 isbased on a simulation result for an electric potential and a currentdensity for such a structure at a magnetic field strength of 0T. Otherparameters that have been chosen for the sake of simulation are: the tubis 6.5 μm deep, 9.7 μm wide (perpendicular to the drawing plane), and 9μm long. Each contact is 1 μm long, and 9.7 μm wide. The bottom of eachtub is highly conductive (e.g. n⁺ doped buried layer, nBL). Note thatthe electronic device (e.g., vertical Hall device) according to theteachings disclosed herein works also if the bottom of the tub isisolated.

During the first clock phase of the spinning current cycle, for which asimulation of an electrical potential at a surface of the Hall effectregions and of the current density is shown in FIG. 7, a voltage of 1Vis applied both between the supply contacts 21 and 22 of the first ringstructure and between the supply contacts 25 and 26 of the second ringstructure. At the ring-contacting contacts 31 to 38, a moderate voltagecomprised between approximately 0.4V and 0.6V may be observed. Thecurrent streamlines indicate that the current distribution issubstantially symmetrical for the purposes of an application of thespinning current scheme.

FIG. 8 shows a graph illustrating, for three different magnetic fieldvalues, the electric potential at a surface of the four Hall effectregions 11 to 14 of the electronic device according to the embodimentshown in FIG. 7. Note that the potential at the contacts 23 and 28 atthe position x=+/−1.7×10⁻⁵ m (+/−17 μm) increases with positive magneticfield whereas the potential at the contacts 24 and 27 at the positionx=+/−0.7×10⁻⁵ m (+/−7 μm) decreases with positive magnetic field. Twodifferential voltages can be tapped: the one at a common mode potentialof around 0.75V and the other at the common mode potential of around0.25V. The magnetic sensitivity is approximately 27.5 mV/V/T. Each ringstructure has a resistance of approximately 4.22 kOhm at a width of 9.7μm.

If we introduce the shorts 81, 82 (=thick broken lines above in FIG. 6)the potentials are pretty similar to what is shown in FIG. 8, yet themagnetic sensitivity decreases slightly to 25.5 mV/V/T, whereas thehigher degree of symmetry in the device reduces the residual offset(=offset, which is left after a spinning current sequence due tonon-linearity of the device and imperfections of the circuit).

The embodiments shown in the following FIGS. 9 to 23 illustrate variousarrangements with respect to the layout of the Hall effect regions 11 to14, the various arrangements differing with respect to 2^(nd) ordereffects, such as amount of wiring/cabling, required space,thermo-electrical effects, self field, matching, etc.

FIG. 9 shows a schematic plan view of an electronic device 100 accordingto an embodiment with four Hall effect regions arranged in a line, i.e.a longitudinal configuration. A corresponding cross-section can bereadily derived from the schematic plan view of FIG. 9 in an analogousmanner as in FIG. 1. FIG. 9 shows the configuration during the firstclock phase of the spinning current cycle. The configuration may bedescribed as follows in condensed form: both tubs of each ring are linedup on a single axis and both rings are lined up on the same axis. Thefirst basic electronic device or ring structure 10-1 comprising the Halleffect regions 11 and 12 is substantially identical to the first ringstructure of the electronic device shown in FIG. 6. The second basicelectronic device or ring structure 10-2 comprising the Hall effectregions 13 and 14 differs from the second ring structure of theelectronic device 10 of FIG. 6 in that the supply contacts 25, 26 andthe sense contacts 27, 28 have swapped their positions, i.e. in FIG. 9the supply contacts 25, 26 are the right contacts of the inner contactsof the Hall effect regions 13 and 14. Two differential sense signals, inparticular two differential voltages, may be measured. A firstdifferential voltage is measured between i) the sense contact 23 formedat the surface of the first Hall effect region 11 of the first basicelectronic device 10-1 and ii) the sense contact 27 formed at thesurface of the first Hall effect region 13 of the second basicelectronic device 10-2. Hence, the differential voltage is measured in abasic electronic device-spanning manner. A second differential voltageis measured between iii) the sense contact 24 formed at the surface ofthe second Hall effect region 11 of the first basic electronic device10-1 and iv) the sense contact 28 formed at the surface of the secondHall effect region 13 of the second basic electronic device 10-2.

Note that the configuration shown in FIG. 9 does not markedly respond toa magnetic field in the y-direction, i.e. the direction in the drawingplane that is perpendicular to the longitudinal axis of the electronicdevice 10. The reason is that a homogeneous magnetic field in they-direction causes the electrical potentials to increase or decrease inthe same manner at the sense contacts that are used to determinerespective differential Hall signals (for example: sense contacts 23 and27 or sense contacts 24 and 28). However, the structure shown in FIG. 9is capable of sensing mechanical stress within the semiconductor crystalin which the structure is formed. Indeed, by reversing the polarity ofthe power supply at one of the rings only, the electronic device may beconfigured to measure either the magnetic field or the mechanicalstress. An electronic device 10, 100 as disclosed herein thus alsoencompasses a mechanical stress sensor. Features that are claimed and/ordescribed in connection with the electronic device for sensing amagnetic field are typically also applicable to the mechanical stresssensor, provided that the above mentioned condition regarding thepolarity of the power supply is fulfilled.

The four tubs 11 to 14 may be arranged in a single line as above, yetthey may also be arranged in a 2×2-matrix as shown in FIGS. 10 to 12.The drawings in FIGS. 10 to 12 show the plan views of the variouselectronic devices 100 in their configurations during operating phase 1;in phase 2 one simply has to exchange supply terminals with senseterminals. All arrangements shown in FIGS. 10 to 12 are substantiallyequivalent with respect to the Hall signal, yet they are different withrespect to thermo-electric and piezo-electric disturbances. Thesearrangements shown in FIGS. 10 to 12 are generated by mere translationof the tubs—no rotation or mirror symmetric placement has beenperformed.

FIG. 10 shows a schematic plan view of an electronic device 100according to an embodiment with four Hall effect regions arranged in aquadrangle. A corresponding cross-section can be readily derived fromthe schematic plan view of FIG. 10 in an analogous manner as in FIG. 1.The configuration shown in FIG. 10 may be regarded as a lateralconfiguration. The first basic electronic device or ring structure 10-1comprises two tubs 11, 12 that are arranged on a line. The second basicelectronic device or ring structure 10-2 comprises two further tubs 13,14 that are arranged on a further line parallel to the line of the firstring structure. The tubs 11 and 13 are substantially aligned to eachother in a direction perpendicular to the above mentioned line and thefurther line. Likewise, the tubs 12 and 14 are substantially aligned toeach other in the direction perpendicular to the line and the furtherline. A first differential voltage is tapped between the aligned tubs 11and 13, in particular the sense contact 23 of the first basic electronicdevice 10-1 and a sense contact 27 of the second basic electronic device10-2. A second differential voltage is tapped between the aligned tubs12 and 14, in particular between the sense contact 24 of the first basicelectronic device 10-1 and the sense contact 28 of the second basicelectronic device 10-2. The differential voltages are measured in abasic electronic device-spanning manner in one embodiment.

FIG. 11 shows a schematic plan view of an electronic device 100according to another embodiment with four Hall effect regions arrangedin a quadrangle. A corresponding cross-section can be readily derivedfrom the schematic plan view of FIG. 11 in an analogous manner as inFIG. 1. The configuration shown in FIG. 11 may be regarded as a lateralconfiguration. The embodiment shown in FIG. 11 is similar to theembodiment shown in FIG. 10 with the following differences: In thesecond basic electronic device 10-2, the polarity of the supply contactsis inversed and the differential voltages are tapped diagonally betweenthe first tub 11 of the first basic electronic device 10-1 and thesecond tub 14 of the second basic electronic device 10-2, as well asbetween the second tub 12 of the first basic electronic device 10-1 andthe first tub 13 of the second basic electronic device 10-2. Thedifferential voltages are measured in a basic electronic device-spanningmanner.

FIG. 12 shows a schematic plan view of an electronic device 100according to an embodiment with four Hall effect regions 11 to 14arranged in a quadrangle and with diagonal ring structures. Acorresponding cross-section can be readily derived from the schematicplan view of FIG. 12 in an analogous manner as in FIG. 1. Theconfiguration shown in FIG. 12 may be regarded as a diagonally offsetconfiguration. The first basic electronic device 10-1 forms a diagonalring structure and comprises the upper left tub 11 and the lower righttub 12. The second basic electronic device 10-2 forms another ringstructure and comprises the upper right tub 13 and the lower left tub14. The differential voltages are measured in a basic electronicdevice-spanning manner. The second Hall effect region 12 islongitudinally and laterally offset with respect to the first Halleffect region 11. Regarding the second basic electronic device 10-2, theHall effect region 14 is longitudinally and laterally offset withrespect to the Hall effect region 13.

Optionally, the embodiments shown in FIGS. 10 to 12 may compriseshorting circuits (or “shorts” or bridging circuits) 81 and 82.

According to the basic electronic device 10 having only a single ringstructure, the first and second Hall effect regions 11, 12 of the singlering structure may be disposed side by side, or laterally offset.Accordingly, the first end of the first Hall effect region and thesecond end of the second Hall effect region may be adjacent, and viceversa. Typically, the first and second Hall effect regions 11, 12 areelongate and have a longitudinal axis. In a side by side arrangement ofthe first and second Hall effect regions 11, 12, the second Hall effectregion 12 is substantially translated with respect to the first Halleffect region 11 in a direction perpendicular to the longitudinal axisof the first Hall effect region 11 and parallel to the surface thereof.

FIG. 13 shows a schematic plan view of an electronic device 100according to a further embodiment responsive to mechanical stress withinthe semiconductor crystal in which the Hall effect regions are formed. Acorresponding cross-section can be readily derived from the schematicplan view of FIG. 13 in an analogous manner as in FIG. 1. The electronicdevice, or mechanical stress sensor, comprises two basic electronicdevices 10-1, 10-2 having collectively four Hall effect regions 11 to 14arranged in a quadrangle. This embodiment has some features in commonwith the embodiment shown in FIG. 10. Deviating from FIG. 10, the tworing structures are substantially identical in the embodiment of FIG.13. Two differential voltages are tapped between the first and thesecond ring structures between sense contacts at substantially the samelocations within the ring structure: the left one of the inner contactsof each tub 11 to 14. Note that a magnetic field may influence theelectric potentials at the sense contacts 23, 24 due to the Hall effect.However, the electric potentials at these sense contacts 23, 24 areinfluenced substantially in the same manner so that the Halleffect-related portions of the electric potentials substantially canceleach other out when a differential signal is determined on the basis ofthe two electric potentials at the sense contacts 23, 24. The magneticfield does not, or only negligibly, influence said differential signal.Instead, the differential signal is mostly a function of the mechanicalstress within the semiconductor crystal. In this manner, the influenceof the Hall effect and of a magnetic field in the output signal of amechanical stress sensor may be reduced. For this reason, the Halleffect regions 11 to 14 that are responsive to a vertical Hall effecthave the effect of substantially cancelling out an influence of amagnetic field on the output signal of the mechanical stress sensor.

It is also possible to arrange the four tubs 11 to 14 in a single columnand there are also several combinations of sequential order (from top tobottom), as will be illustrated in more detail below (FIGS. 22 and 23).

FIG. 14 shows a schematic plan view of an electronic device 10 accordingto an embodiment with four Hall effect regions 11 to 14. A correspondingcross-section can be readily derived from the schematic plan view ofFIG. 14 in an analogous manner as in FIG. 1. The configuration shown inFIG. 14 may be regarded as an angled configuration and is responsive tomechanical stress. The two Hall effect regions 11 and 12 are arranged onthe same line and belong to a first basic electronic device 10-1 forminga ring structure. The two Hall effect regions 13 and 14 are arranged onanother, non-parallel line and belong to a second basic electronicdevice 10-2 forming a ring structure. In particular, the Hall effectregions 13, 14 of the second basic electronic 10-2 device are arrangedat an angle of 90 degrees (other angles are possible) with respect tothe Hall effect regions 11, 12 of the first basic electronic device10-1. Two differential voltages are measured in a basic electronicdevice-spanning manner. Typically, the output signals are linearcombinations of both magnetic field components parallel to the surfaceof the die. The coefficients of these linear combinations depend on theangles between the lines along which both rings are arranged.

FIG. 15 shows a schematic plan view (top view) of an electronic device100 according to an embodiment with four Hall effect regions 11 to 14similar to the embodiment shown in FIG. 14, i.e. an angledconfiguration. However, the spinning current contacts of the secondbasic electronic device 10-2 in FIG. 15 have different functions duringthe first clock phase than in FIG. 14. In particular, the supplycontacts in the second basic electronic device 10-2 are, during thefirst operating phase of the spinning current scheme, the secondcontacts from the top in the respective Hall effect region 13, 14. Afirst differential voltage U1 is measured between a sense contact of thefirst tub 11 of the first basic electronic device 10-1 and a sensecontact of the first tub 13 of the second basic electronic device 10-2.A second differential voltage U2 is measured between a sense contact ofthe second tub 12 of the first basic electronic device 10-1 and a sensecontact of the second tub 14 of the second basic electronic device 10-2.The first differential voltage U1 is proportional to Bx+By, i.e. a firstlinear combination of the magnetic field components in the x-directionand in the y-direction. The second differential voltage U2 isproportional to −Bx−By, i.e. a second linear combination of the magneticfield components in the x-direction and in the y-direction. Note that U2is substantially equal to the inverse of U1, i.e., U2=−U1 (wheninaccuracies are neglected). A corresponding cross-section can bereadily derived from the schematic plan view of FIG. 15 in an analogousmanner as in FIG. 1.

FIG. 16 shows a schematic top view of an electronic device 100 accordingto an embodiment, wherein each basic electronic device 10-1, 10-2comprises two Hall effect regions disposed at an angle of 90 degrees(other angles are possible) to each other. Hence, this embodiment usesan arrangement, where the two tubs of each ring or basic electronicdevice 10-1, 10-2 are rotated with respect to each other by e.g. 90degrees in the layout. Two differential voltages U1 and U2 may bemeasured. In the case depicted in FIG. 16, the first differentialvoltage U1 is measured between the tub 11 belonging to the first basicelectronic device 10-1 and the tub 13 belonging to the second electronicdevice 10. The second differential voltage U2 is measured between thetub 12 belonging to the first basic electronic device 10-1 and the tub14 belonging to the second basic electronic device 10-2. The firstdifferential voltage U1 is proportional to the term 2By. The seconddifferential voltage is proportional to the term −2Bx. A correspondingcross-section can be readily derived from the schematic plan view ofFIG. 16 in an analogous manner as in FIG. 1.

The second ring may also be rotated as a whole with respect to the firstone by some angle: then U2 is not proportional to 2Bx but some linearcombination of the magnetic field components Bx and By, depending on theexact angular position of the second ring (basic electronic device 10-2)with respect to the first ring (basic electronic device 10-1). Havingseveral arrangements like this at different angular positions the systemcan reconstruct Bx and By by proper linear combinations of the signalsdelivered by these systems. For all these arrangements it is possible toshift the position of each tub as a pure translation, in order toarrange them in columns or lines or even in an interdigital arrangement.This may improve matching and errors due to thermo-electric voltages.

Note that the output signals may be in voltage domain (as given in FIGS.15 and 16, such as U1, U2, . . . )—however, one may also short the sensepins and measure the short circuit currents I1, I2, . . . which carriesthe same information as the voltage, according to U1=Ri1*I1, U2=Ri2*I2,. . . with Ri1, Ri2 denoting the internal resistances of the devices inthe respective electrical configurations. If the current-voltagecharacteristics of the devices (at zero magnetic field) are linear, U1and I1 correspond to each other and give the same residual offset over afull spinning current cycle. Yet, if the current-voltage characteristicsof the devices are nonlinear, the residual offset of the signals incurrent domain should typically be more accurate than in voltage domain,because the nonlinear current-voltage characteristics reduce the effectof nonlinearity.

FIG. 17 shows a schematic plan view of an electronic device 100according to an embodiment similar to the embodiment shown in FIG. 16. Adifference between the embodiments shown in FIGS. 16 and 17 is that thefirst and second contacts of the tubs 11 to 14 are larger than thesupply/sense contacts 21 to 28. In both embodiments according to FIGS.16 and 17, the tubs belonging to the same basic electronic device 10-1,10-2 are arranged on different axes that form an angle of e.g. 90degrees. A corresponding cross-section can be readily derived from theschematic plan view of FIG. 17 in an analogous manner as in FIG. 1.

FIG. 18 shows a schematic plan view of an electronic device 10 accordingto an embodiment comprising four Hall effect regions 11 to 14 arrangedin a quadrangle. A corresponding cross-section can be readily derivedfrom the schematic plan view of FIG. 18 in an analogous manner as inFIG. 1. Regarding the arrangement of the first and second basicelectronic devices 10-1, 10-2, the embodiment shown in FIG. 18 has alongitudinal configuration because the right basic electronic device10-2 is provided in an extension of the longitudinal axis of the left(first) basic electronic device 10-2. A first basic electronic device10-1 comprises the tubs 11 and 12 that are laterally displaced withrespect to each other. A second basic electronic device 10-2 comprisesthe tubs 13 and 14 that are also laterally displaced with respect toeach other. The two basic electronic devices 10-1, 10-2 are arranged ona line extending along a longitudinal direction of the four tubs 11 to14, i.e. the two ring structures are aligned in the longitudinaldirection of the four tubs 11 to 14. The embodiment of FIG. 18 may bebriefly described as follows: both tubs of each basic electronic device(or ring) 10-1, 10-2 are parallel to each other but on different linesand both rings are next to each other. A more elaborate description ofthe embodiment shown in FIG. 18 reveals that the electronic devicecomprises a first Hall effect region 11, a second Hall effect region 12,a third Hall effect region 13, and a fourth Hall effect region 14 thatare isolated from each other. Each Hall effect region 11 to 14 comprisesa first contact, a second contact, a supply contact, and a sense contactin or on surfaces of the respective Hall effect region 11 to 14. Thefirst contact 33 of the second Hall effect region 12 is connected to thesecond contact 32 of the first Hall effect region 11 and the firstcontact 31 of the first Hall effect region 11 is connected to the secondcontact 34 of the second Hall effect region 12, so that two currentpaths exist between the supply contact 21 of the first Hall effectregion 11 and the supply contact 22 of the second Hall effect region 12.In a similar manner the first contact 37 of the fourth Hall effectregion 14 is connected to the second contact 36 of the third Hall effectregion 13 and the first contact 35 of the third Hall effect region 13 isconnected to the second contact 38 of the fourth Hall effect region, sothat two current paths exist between the supply contact 25 of the thirdHall effect region 13 and the supply contact 26 of the fourth Halleffect region 14. The supply contacts 21, 22, 25, 26 and the sensecontacts 23, 24, 27, 28 (in the first operating phase) are arranged in asequence along each one of the current paths such that there is onesense contact of the sense contacts between two of the supply contacts.A first differential sense signal is tapped between the sense contacts23 and 27 of the first and third Hall effect regions 11 and 13,respectively, and a second differential sense signal is tapped betweenthe sense contacts 24 and 28 of the second and fourth Hall effectregions 12 and 14, respectively.

FIG. 19 shows a schematic top view of an electronic device 100 accordingto an embodiment similar to the one shown in FIG. 18. Again, theconfiguration of the electronic device 100 during the first clock phaseis shown. The configuration during the second clock phase is shown inFIG. 21 and can be deduced by swapping the supply contacts and the sensecontacts. Both wells or tubs 11, 12 of the first basic electronic device10-1 (left ring) are arranged in a two-dimensional way. In the samemanner, the wells or tubs 13, 14 of the second basic electronic device(right ring) 10-2 are arranged in a two-dimensional way. The potentialdistribution in the second basic electronic device 10-2 is substantiallya mirrored version of the potential distribution in the first basicelectronic device 10-2 with respect to a mirror axis (or symmetry axis)located to the right of the first basic electronic device 10-1, i.e.substantially adjacent and parallel to the second connection 42. Theconnections 41 to 44 do not, in the embodiment shown in FIG. 19,comprise wires or strip lines, but are provided by extensions orprolongations of the ring-contacting contacts 31 to 38 so as to bridge agap between the first and second Hall effect regions 11 and 12 of thefirst basic electronic device 10-1 and, mutatis mutandis, between thefirst and second Hall effect regions 13 and 14 of the second basicelectronic device 10-2. A corresponding cross-section can be readilyderived from the schematic plan view of FIG. 19 in an analogous manneras in FIG. 1.

A differential signal on high common mode is tapped between the sensecontacts 23 and 27. The sense contact 23 is part of the first basicelectronic device 10-1 and the sense contact 27 is part of the secondbasic electronic device 10-2. Moreover, a differential signal on lowcommon mode is tapped between the sense contacts 24 (part of the firstbasic electronic device 10-1) and 28 (part of the second basicelectronic device 10-2).

FIG. 20 shows a schematic top view of an electronic device according toan embodiment combining the embodiments shown in FIG. 2 and FIG. 19. Acorresponding cross-section can be readily derived from the schematicplan view of FIG. 20 in an analogous manner as in FIG. 1. Starting outat the embodiment shown in FIG. 19, the left and right tubs may becombined to save space. This leads to two long tubs 11, 12. The firstbasic electronic device 10-1 (left ring) and the second basic electronicdevice 10-2 (right ring) are shorted at the ring-contacting contacts 32,33, 35, and 38 via the connections 42 and 43 which are formed as onepiece in the embodiment shown in FIG. 20. In this last case the twoouter ring-contacting contacts 31 and 36 may or may not be shorted. Alsothe two spinning current contacts or terminals 21 and 25 where currentis injected in a specific clock phase may be shorted (analogously,spinning current contacts 22 and 26 may be shorted during the secondclock phase).

The embodiment shown in FIG. 20 may also be described as follows: Thefirst Hall effect region 11 and the third Hall effect region 13 merge atone of their first ends and second ends, respectively. Also the secondHall effect region 12 and the fourth Hall effect region 14 merge at oneof their first ends and second ends, respectively.

FIG. 21 shows a schematic top view of the electronic device 100according to the embodiment shown in FIG. 19 during a second clockphase. A corresponding cross-section can be readily derived from theschematic plan view of FIG. 21 in an analogous manner as in FIG. 1. Thecurrent is supplied in the following way: the current enters at thespinning current contacts 23 and 27 (now functioning as supplycontacts). The spinning current contacts 24 and 28, that also functionas supply contacts during the second clock phase, are connected to aground potential. A first differential signal is tapped between thespinning current contacts 21 and 25, now functioning as sense contacts.The first differential contacts 21 and 25 are both on a high commonmode. A second differential signal is tapped between the spinningcurrent contacts 22 and 26, now functioning as sense contacts. Thesecond differential contacts 22 and 26 are both on a low common mode.

FIG. 22 shows a schematic plan view of an electronic device 100according to an embodiment comprising four Hall effect regions arrangedin a column. A corresponding cross-section can be readily derived fromthe schematic plan view of FIG. 22 in an analogous manner as in FIG. 1.A first basic electronic device 10-1 comprises the Hall effect regions11 and 12. A second basic electronic device 10-2 comprises the Halleffect regions 13 and 14. The second basic electronic device 10-2 isarranged laterally displaced with respect to the first basic electronicdevice 10-1. Two differential signals are tapped in a basic electronicdevice-spanning manner. The first differential signal is measuredbetween the sense contact 23 at the first tub 11 of the first basicelectronic device 10-1 (upper ring in FIG. 22) and the sense contact 27at the first tub 13 of the second basic electronic device 10-2 (lowerring in FIG. 22). The second differential signal is measured between thesense contact 24 at the second tub 12 of the first basic electronicdevice 10-1 (upper ring) and the sense contact 28 of the second tub ofthe second basic electronic device 10-2 (lower ring).

FIG. 23 shows a schematic plan view of an electronic device 100according to another embodiment comprising four Hall effect regionsarranged in a column wherein the basic electronic device 10-1, 10-2 areinterleaved or concentric with respect to each other, i.e. a concentricconfiguration. A corresponding cross-section can be readily derived fromthe schematic plan view of FIG. 23 in an analogous manner as in FIG. 1.A first basic electronic device 10-1 comprises the tubs 11 and 12 and asecond basic electronic device 10-2 comprises the tubs 13 and 14. Thefirst basic electronic device 10-1 is an outer ring which surrounds thesecond basic electronic device 10-2, which consequently forms an innerring. A first differential signal is measured between a sense contact 23at the first tub 11 of the first basic electronic device 10-1 (outerring in FIG. 23) and the sense contact 27 at the first tub 13 of thesecond basic electronic device 10-2 (inner ring in FIG. 23). The seconddifferential signal is measured between the sense contact 24 at thesecond tub 12 of the first basic electronic device 10-1 (outer ring) andthe sense contact 28 of the second tub of the second basic electronicdevice 10-2 (inner ring).

FIG. 24 shows two schematic top views of an electronic device 100according to an embodiment of the teachings disclosed herein during afirst phase and a second phase of a measuring cycle, the electronicdevice comprising four Hall effect regions, each having a singlespinning current contact. Corresponding cross-sections can be readilyderived from the schematic plan views of FIG. 24 in an analogous manneras in FIG. 1. The embodiment uses four isolated tubs 11 to 14, eachhaving three contacts: two outer contacts per tub and one inner contactper tub. The inner contact is used as a sense-terminal or asupply-terminal in consecutive phases of the spinning current Hall probesequence. The four tubs are wired together with their outer contacts toform a ring. The first tub 11 comprises the two ring-contacting contacts31 and 32 as the outer contacts and the spinning current contact 23 asthe inner contact. The second tub 12 comprises the two ring-contactingcontacts 33 and 34 as the outer contacts and the spinning currentcontact 21 as the inner contact. The third tub 13 comprises the tworing-contacting contacts 35 and 36 as the outer contacts and thespinning current contact 24 as the inner contact. The fourth tub 14comprises the two ring-contacting contacts 37 and 38 as the outercontacts and the spinning current contact 22 as the inner contact. Onedifferential signal is measured during the first clock phase between thesense contacts 23 and 24.

In the second clock phase, the ring-contacting contacts 31 to 38 are notchanged compared to the first clock phase. However, the spinning currentcontacts 21 to 24 change their respective functions from supply contactto sense contact, and vice versa. Hence, an electric current is now fedto the first tub 11 at spinning current contact 23 to flow through thefour tubs 11, 12, 13, 14 and the connections 41, 42 to the supplycontact 24 where the current exits the tub 13. As explained above, thecurrent is distributed in a substantially uniform manner to follow afirst conducting path in a clockwise direction via connection 41 and tofollow another conducting path in a counter clockwise direction via theconnection 42. The arrangement assures that current can pass underneaththe sense contacts in order to make best use of the Hall effect. At thesame time the structure is substantially perfectly symmetric ifsense—and supply-terminals are exchanged in order to cancel the offset.

In the embodiment shown in FIG. 24 the at least two supply contacts 21,22, and the at least two sense contacts 23, 24 are formed in or on thesurfaces of the Hall effect regions 11 to 14 in addition to thecorresponding first contacts 31, 33, 35, 37 and the corresponding secondcontacts 32, 34, 36, 38 so that at least three contacts are formed in oron the surface of each Hall effect region 11 to 14. A Hall effectregion, in or on a surface of which a sense contact is formed (i.e.,Hall effect regions 11 and 13 in the first operating phase of thespinning current cycle), is between two Hall effect regions, in or onthe surfaces of which supply contacts are formed (i.e., Hall effectregions 12 and 14 in the first operating phase of the spinning currentcycle).

As can be seen in FIG. 24, the electronic device 100 comprises four Halleffect regions 11 to 14 that are isolated from each other. Each of thefour Hall effect regions 11 to 14 comprises a first contact and a secondcontact in or on a surface of the respective Hall effect region. A firstcontact 33, 35, 37 of the (k+1)-th Hall effect region is connected to asecond contact 32, 34, 36, respectively, of the k-th Hall effect regionfor k=1 to 3. A first contact 31 of the first Hall effect region 11 isconnected to a second contact 38 of the fourth Hall effect region 14.Each of the four Hall effect regions 11 to 14 further comprises one of asupply contact 21, 22 and a sense contact 23, 24 in or on the surface ofthe Hall effect region, the supply contact 21, 22 or the sense contact23, 24 being arranged between the first contact 31, 33, 35, 37 and thesecond contact 32, 34, 36, 38 of the respective Hall effect region. AHall effect region in or on the surface of which a supply contact isformed is connected via its first and second contacts to two Hall effectregions in or on the surfaces of which a sense contact is formed,respectively, so that the supply contacts and the sense contacts arearranged in a sequence along a current path between at least two supplycontacts 21, 22 such that there is one sense contact 23 or 24 betweenthe at least two supply contacts 21, 22. Each Hall effect region 11 to14 comprises at most one of the at least two supply contacts 21, 22. Anadvantage of the electronic device shown in FIG. 24 is its high degreeof symmetry. In particular, the common mode voltages in both spinningcurrent phases is substantially identical.

FIG. 25 shows a schematic cross sectional view of an electronic device10 according to another embodiment of the teachings disclosed hereinhaving 2-contact tubs that are connected to a ring. Furthermore, FIG. 25also shows a simulated distribution of an electrical potential and asimulated current density distribution. A corresponding plan view can bereadily derived from the schematic cross-section of FIG. 25 in ananalogous manner as in FIG. 1.

In the schematic cross section it can be seen that an electric currentis supplied to the electronic device via the spinning current contact21. The electric current exits the electronic device at the spinningcurrent contacts 22 of the tubs 13 and 14. Assuming a particularnon-zero magnetic field in the y-direction (perpendicular to the drawingplane), the current is pushed towards the bottom of the tubs whentraversing the respective tub from right to left (as in tubs 11 and 13).In contrast, the current is pushed towards the top of the tubs and thusclose to the sense contacts when it traverses the respective tub fromleft to right (as in tubs 12 and 14).

In this embodiment, the sense contacts and the ring-contacting contacts23, 24 coincide. In other words, each supply contact of the at least twosupply contacts 21, 22 coincides with at least one of the first andsecond contacts of at least one Hall effect region (i.e., thering-contacting contacts), and wherein each sense contact of the atleast two sense contacts 23, 24 coincides with at least one of the firstand second contacts of at least one Hall effect region. The electronicdevices comprises four Hall effect regions so that each of the Halleffect regions has two of the at least eight contacts mentioned in thesummary. Typically, each Hall effect region has one supply contact andone sense contact. Hence, a sense contact is between two supply contactswhen contemplating the sequence of contacts along a current path (asense that connects two Hall effect regions counts as one sensecontact—that is, the sense contact 23 at the Hall effect region 11 andthe sense contact 24 at the Hall effect region 13 count as one sensecontact). Therefore, during the first operating phase of the spinningcurrent scheme a differential signal is measured between the first ringconnection C1 which connects the tubs 11 and 14, and the second ringconnection C3 which connects the tubs 12 and 13.

A linearized model has been used for the purpose of simulation. At 1Vsupply voltage applied between the contacts 21 and 22, the voltageobserved at C1 (with respect to a reference potential) is substantiallyequal to the voltage observed at C3 (with respect to the same referencepotential), i.e. V_(C1)=V_(C3)=488.483 mV at By=0, i.e., no magneticfield in the y-direction. In contrast, at a magnetic field strength inthe y-direction of By=1T, the voltage difference at C3 compared to thezero-magnetic field case is V_(C3)−488.483 mV=−0.09626 mV. At the sametime, the voltage difference at C1 compared to the zero-magnetic fieldcase is V_(C1)−488.483 mV=0.1136 mV. Hence, the total magneticsensitivity is 113.6 μV−(−96.26 μV)=210 μV/V/T which amounts to arelatively poor magnetic sensitivity. Presumably, the reason for thepoor magnetic sensitivity of the 2-contact-per-tub electronic device isthe fact that the Lorentz force is not able to have a sufficientinfluence on the signal: The Lorentz force is merely capable ofextending the current streamlines slightly towards the depth or urgethem slightly to the surface; however, the Lorentz force does not appearto be able to cause a current distribution among two contacts.

FIG. 26 shows a graph illustrating the electrical potential at twodifferent contacts over the magnetic field strength. The upper lineindicates the evolution of the voltage over the magnetic field strengthat the contact which is located at x=1.6×10⁻⁵ m, i.e. contact 23 whichis connected to connection C1. The lower line indicates the evolution ofthe voltage over the magnetic field strength at the contact which islocated at x=1.0×10⁻⁶ m, i.e. contact 24 which is connected toconnection C3. It can be seen that at a magnetic field strength of 1T,the voltage difference between C1 and C3 is approximately 2×10⁻⁴V=200μV.

With all above circuits one may also change the sign of the supplyvoltage and reverse the output voltage simultaneously: this gives a3^(rd) and 4^(th) clock phase as is usual in the full spinning currentclock cycle. Moreover, the electronic device may further comprise aspinning current controller configured to control the at least onespinning current contact regarding a function thereof as a power supplycontact or a sense contact during a particular time interval.

FIG. 27 shows a schematic flow chart of a sensing method according to anembodiment of the disclosed teachings. The method comprises an action 92during which a power supply gets connected between a first supplycontact formed in or on a surface of a first Hall effect region and asecond supply contact formed in or on a surface of a n-th Hall effectregion. A first contact of the (k+1)-th Hall effect region is connectedto a second contact of the k-th Hall effect region for k=1 to n−1.Furthermore, the first contact of the first Hall effect region isconnected to the second contact so that an electric current provided bythe power supply flows via two current paths from the first supplycontact to the second supply contact. For the time being, the powersupply stays connected to the first and second supply contacts.

Then, as indicated by the box with the reference numeral 94, sensesignals are sensed at a first sense contact of one of the n Hall effectregions and at a second sense contact of another one of the n Halleffect regions. The first sense contact is formed in or on the surfaceof said Hall effect region of the n Hall effect regions. The secondsense contact is formed in or on the surface of said other Hall effectregion of the n Hall effect regions. Each Hall effect region has at mostone of the at least two sense contacts, i.e., a Hall effect region mayhave zero or one sense contacts (a single sense contact may be split upinto two or more partial, interconnected contacts). The action ofsensing a sense signal may comprise sampling a value of an electricpotential at the sense contact (referred to a reference potential) ormeasuring an electric current flowing into the sense contact or out ofthe sense contact. The sense signal thus acquired may be temporarilystored or supplied to a sample-and-hold circuit until it is used duringfurther processing.

The method continues with swapping, at an action 96 of the sensingmethod, the temporary functions of the first supply contact and thefirst sense contact. Likewise, the temporary functions of the secondsupply contact and the second sense contact are swapped. The swapping ofthe temporary functions may be summarized as follows: the (former) firstsupply contact becomes the new first sense contact. The (former) secondsupply contact becomes the new second sense contact. The (former) firstsense contact becomes the new first supply contact. The (former) secondsense contact becomes the new second supply contact. The swappingresults in the power supply being connected between the former firstsense contact and the former second sense contact. The electric currentflows from the former first sense contact to the former second sensecontact via the n Hall effect regions.

With respect to the swapping of the supply contacts and the sensecontacts it should be noted that the supply contacts and the sensecontacts are typically multipurpose contacts that may provide atemporary function as a supply contact during a first operating phase ofa spinning current scheme and another temporary function as a sensecontact during a second operating phase of the spinning current scheme,or vice versa. This concept also applies to a majority of theembodiments relating to an electronic device, to a Hall effect device,or to a mechanical stress sensor. In other words, the denomination of acontact as a supply contact or a sense contact relates to a temporaryfunction of the contact. The temporary function of a supply/sensecontact may change during the course of one cycle of the spinningcurrent scheme.

At an action 98 sense signals at the former first supply contact (newfirst sense contact) and the former second supply contact (new secondsense contact) are sensed.

An output signal is then determined on the basis of the sense signals atthe first sense contact, the second sense contact, the former firstsupply contact, and the former second supply contact, as indicated inthe flow diagram at the box with the reference numeral 99. The outputsignal may be a linear combination of the sense signals that have beenacquired during the actions 94 and 97. In this manner, an effect ofasymmetries of the n Hall effect regions on the output signal can beeffectively reduced which in turn leads to a reduce zero point error.

Although some aspects have been described in the context of anapparatus, it is clear that these aspects also represent a descriptionof the corresponding method, where a block or device corresponds to amethod step or a feature of a method step. Analogously, aspectsdescribed in the context of a method step also represent a descriptionof a corresponding block or item or feature of a correspondingapparatus. Some or all of the method steps may be executed by (or using)a hardware apparatus, like for example, a microprocessor, a programmablecomputer or an electronic circuit. In some embodiments, some one or moreof the most important method steps may be executed by such an apparatus.

The above described embodiments are merely illustrative for theprinciples of the present invention. It is understood that modificationsand variations of the arrangements and the details described herein willbe apparent to others skilled in the art. It is the intent, therefore,to be limited only by the scope of the impending patent claims and notby the specific details presented by way of description and explanationof the embodiments herein.

What is claimed is:
 1. An electronic device comprising: an integernumber of n Hall effect regions, with n>1, wherein the n Hall effectregions are isolated from each other; wherein the electronic devicecomprises at least eight contacts in or on surfaces of the n Hall effectregions, wherein the contacts comprise a first and a second contact ofeach Hall effect region; wherein a first contact of the (k+1)-th Halleffect region is connected to a second contact of the k-th Hall effectregion for k =1 to n−1, and a first contact of the first Hall effectregion is connected to a second contact of the n-th Hall effect region;wherein the at least eight contacts comprise at least two contactsconfigured to function as supply contacts during a first operating phaseof a spinning current scheme and to function as sense contacts during asecond phase of the spinning current scheme and at least two contactsconfigured to function as sense contacts during the first operatingphase of the spinning current scheme and to function as supply contactsduring the second operating phase of the spinning current scheme;wherein each Hall effect region comprises one of the at least two supplycontacts; and wherein each Hall effect region comprises one of the atleast two sense contacts.
 2. The electronic device according to claim 1,wherein n=2 so that the number of n Hall effect regions comprises afirst Hall effect region and a second Hall effect region, wherein one ofthe at least two supply contacts is formed in or on the surface of thefirst Hall effect region and another one of the at least two supplycontacts is formed in or on the surface of the second Hall effectregion, and wherein one of the at least two sense contacts is formed inor on the surface of the first Hall effect region and another one of theat least two sense contacts is formed in or on the surface of the secondHall effect region.
 3. The electronic device according to claim 2,wherein the first Hall effect region comprises a first end and a secondend, and wherein the second Hall effect region comprises a first end anda second end, wherein the first and second contacts of the first andsecond Hall effect regions are closer to one of the first end and thesecond end of a corresponding one of the first and second Hall effectregions than the at least two supply contacts and the at least two sensecontacts, respectively.
 4. The electronic device according to claim 2,wherein the first and second Hall effect regions each comprise a firstend and a second end, and wherein the first and second contacts of thefirst and second Hall effect regions are farther away from at least oneof the first and second ends of a corresponding one of a first andsecond Hall effect regions than at least one of the supply contacts andthe sense contacts.
 5. The electronic device according to claim 1,wherein n=4, wherein the at least two supply contacts and the at leasttwo sense contacts are formed in or on the surfaces of the Hall effectregions in addition to the corresponding first and second contacts sothat at least three contacts are formed in or on the surface of eachHall effect region, and wherein a Hall effect region, in or on a surfaceof which a sense contact is formed, is electrically connected, by meansof the first and second contacts, between two Hall effect regions, in oron the surfaces of which supply contacts are formed.
 6. The electronicdevice according to claim 1, wherein n=4, wherein each supply contact ofthe at least two supply contacts coincides with at least one of thefirst and second contacts of at least one Hall effect region, andwherein each sense contact of the at least two sense contacts coincideswith at least one of the first and second contacts of at least one Halleffect region.
 7. The electronic device according to claim 1, whereinthe electronic device is symmetric with respect to at least one centerplane.
 8. The electronic device according to claim 1, further comprisingat least one floating contact formed in or on the surface of at leastone of the Hall effect regions.
 9. The electronic device according toclaim 1, wherein each Hall effect region comprises a first end and asecond end, and wherein at least two of the Hall effect regions aredisposed side by side so that the first end of the one of the at leasttwo Hall effect regions is adjacent to the second end of an adjacentHall effect region, and vice versa.
 10. The electronic device accordingto claim 1, wherein at least two of the Hall effect regions are disposedalong a line.
 11. The electronic device according to claim 1, wherein atleast two of the Hall effect regions are disposed at a non-zero anglewith respect to each other.
 12. The electronic device according to claim1, wherein at least one of the Hall effect regions is longitudinally andlaterally offset with respect to at least one other Hall effect region.13. The electronic device according to claim 1, wherein the Hall effectregions are substantially identical with respect to at least one oflateral geometry, vertical geometry, material, and material properties.14. The electronic device according to claim 1, wherein a spacingbetween adjacent contacts in a Hall effect region is on the order of⅕^(th) to 5 times of a depth of the Hall effect region.
 15. Theelectronic device according to claim 1, wherein a size of each contactin a length direction with respect to a corresponding Hall effect regionis on the order of ⅕^(th) to 5 times of a depth of the correspondingHall effect region.
 16. The electronic device according to claim 1,wherein at least one contact of the first and second contacts, the atleast two supply contacts and the at least two sense contacts are ohmiccontacts.
 17. The electronic device according to claim 1, furthercomprising a spinning current controller configured to control the atleast two supply contacts and the at least two sense contacts inaccordance with a spinning current scheme regarding an operatingphase-defined function of an individual contact as one of the two supplycontacts or one of the two sense contacts.
 18. An electronic devicecomprising: an integer number of n Hall effect regions, with n>1,wherein the n Hall effect regions are isolated from each other; whereinthe electronic device comprises at least eight contacts in or onsurfaces of the n Hall effect regions, wherein the contacts comprise afirst and a second contact of each Hall effect region; wherein a firstcontact of the (k+1)-th Hall effect region is connected to a secondcontact of the k-th Hall effect region for k=1 to n−1, and a firstcontact of the first Hall effect region is connected to a second contactof the n-th Hall effect region; wherein the at least eight contactscomprise at least two supply contacts and at least two sense contacts;wherein each Hall effect region comprises one of the at least two supplycontacts; wherein each Hall effect region comprises one of the at leasttwo sense contacts, and wherein all contacts in or on the surface of aHall effect region are arranged along a straight line.
 19. An electronicdevice comprising: an integer number of n Hall effect regions, with n>1,wherein the n Hall effect regions are isolated from each other; whereinthe electronic device comprises at least eight contacts in or onsurfaces of the n Hall effect regions, wherein the contacts comprise afirst and a second contact of each Hall effect region; wherein a firstcontact of the (k+1)-th Hall effect region is connected to a secondcontact of the k-th Hall effect region for k=1 to n−1, and a firstcontact of the first Hall effect region is connected to a second contactof the n-th Hall effect region; wherein the at least eight contactscomprise at least two supply contacts and at least two sense contacts;wherein each Hall effect region comprises one of the at least two supplycontacts; wherein each Hall effect region comprises one of the at leasttwo sense contacts, and wherein each Hall effect region has a length anda width perpendicular to the length, with the length being larger thanthe width.
 20. An electronic device comprising: first and secondelectronic devices, wherein each of the first and second electronicdevices comprise: an integer number of n Hall effect regions, with n>1,wherein the n Hall effect regions are isolated from each other; whereinthe electronic device comprises at least eight contacts in or onsurfaces of the n Hall effect regions, wherein the contacts comprise afirst and a second contact of each Hall effect region; wherein a firstcontact of the (k+1)-th Hall effect region is connected to a secondcontact of the k-th Hall effect region for k=1 to n−1, and a firstcontact of the first Hall effect region is connected to a second contactof the n-th Hall effect region; wherein the at least eight contactscomprise at least two supply contacts and at least two sense contacts;wherein each Hall effect region comprises one of the at least two supplycontacts; and wherein each Hall effect region comprises one of the atleast two sense contacts; and a sense signal evaluator configured to beconnected to a sense contact of the first electronic device and to asense contact of the second electronic device, and further configured toprocess a differential sense signal that is based on first and secondsense signals provided at said sense contacts, wherein the firstelectronic device and the second electronic device are disposed relativeto each other according to one of the following configurations: alongitudinal configuration, a lateral configuration, an angledconfiguration, a diagonally offset configuration, and a concentricconfiguration.
 21. The electronic device according to 20, wherein theelectronic device is a Hall effect device, and wherein the at least twosense contacts are arranged relative to the at least two supply contactsin a manner that an electric current within a Hall effect region passingby a first one of the at least two sense contacts has a substantiallyopposite direction to an electric current within another Hall effectregion passing by a second one of the at least two sense contacts,whereby the Hall effect device is sensitive to a magnetic field parallelto the surfaces of the Hall effect regions and perpendicular to saiddirections of electric current flow.
 22. The electronic device accordingto claim 20, wherein the electronic device is a mechanical stresssensor, and wherein the at least two sense contacts are arrangedrelative to the at least two supply contacts in a manner that anelectric current within a Hall effect region passing by a first one ofthe at least two sense contacts has substantially the same direction asan electric current within another Hall effect region passing by asecond one of the at least two sense contacts, whereby the mechanicalstress sensor is sensitive to a mechanical stress within the Hall effectregions.